Specify the location of the CVS checkout to use for the export. This
option does not require GIT_DIR to be set before execution if the
current directory is within a git repository. The default is the
value of cvsexportcommit.cvsdir.

-W

Tell cvsexportcommit that the current working directory is not only
a Git checkout, but also the CVS checkout. Therefore, Git will
reset the working directory to the parent commit before proceeding.